The paper gives a quantitative insight into the vulnerability of existing masonry chimneys located in Spain, accounting for horizontal loads, geometry and material deterioration. During the past two centuries, the industrialization process gave rise to a quick increase in the construction of chimneys, which were made almost exclusively by brickwork but present an almost infinite variety of geometries. Nowadays such structures are not used anymore as industrial artifacts, but they belong to the historical heritage and are constantly subjected to natural hazards. To their conservation, a high priority exists, because their specificities and their complex structural behavior are unique. A large survey of chimneys in terms of geometry, possible...